diff --git a/test/Driver/filelists.swift b/test/Driver/filelists.swift
index 4152a18e42c1d..2af7870f3bded 100644
--- a/test/Driver/filelists.swift
+++ b/test/Driver/filelists.swift
@@ -6,7 +6,7 @@
 // RUN: %empty-directory(%t)
 // RUN: touch %t/a.swift %t/b.swift %t/c.swift
 
-// RUN: (cd %t && %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -emit-module ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json 2>&1 | %FileCheck %s)
+// RUN: cd %t && %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -emit-module ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json 2>&1 | %FileCheck %s
 
 // CHECK-NOT: Handled
 // CHECK: Handled a.swift
@@ -42,10 +42,10 @@
 // RUN: %empty-directory(%t/bin)
 // RUN: ln -s %S/Inputs/filelists/fake-ld.py %t/bin/ld
 
-// RUN: (cd %t && %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -c ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1 2>&1 | %FileCheck -check-prefix=CHECK-WMO-THREADED %s)
-// RUN: (cd %t && %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -c ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1 -embed-bitcode 2>&1 | %FileCheck -check-prefix=CHECK-WMO-THREADED %s)
+// RUN: cd %t && %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -c ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1 2>&1 | %FileCheck -check-prefix=CHECK-WMO-THREADED %s
+// RUN: cd %t && %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -c ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1 -embed-bitcode 2>&1 | %FileCheck -check-prefix=CHECK-WMO-THREADED %s
 // RUN: %empty-directory(%t/tmp)
-// RUN: (cd %t && env TMPDIR="%t/tmp/" %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -c ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1 -save-temps 2>&1 | %FileCheck -check-prefix=CHECK-WMO-THREADED %s)
+// RUN: cd %t && env TMPDIR="%t/tmp/" %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -c ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1 -save-temps 2>&1 | %FileCheck -check-prefix=CHECK-WMO-THREADED %s
 // RUN: ls %t/tmp/sources-* %t/tmp/outputs-*
 
 // CHECK-WMO-THREADED-NOT: Handled
@@ -60,17 +60,17 @@
 // CHECK-WMO-THREADED-NOT: Handled
 
 // RUN: mkdir -p %t/tmp-fail/
-// RUN: (cd %t && env TMPDIR="%t/tmp-fail/" not %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/fail.py -c ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1)
+// RUN: cd %t && env TMPDIR="%t/tmp-fail/" not %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/fail.py -c ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1
 // RUN: not ls %t/tmp-fail/sources-*
 // RUN: not ls %t/tmp-fail/outputs-*
 
 // RUN: mkdir -p %t/tmp-crash/
-// RUN: (cd %t && env TMPDIR="%t/tmp-crash/" not %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/crash.py -c ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1)
+// RUN: cd %t && env TMPDIR="%t/tmp-crash/" not %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/crash.py -c ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1
 // RUN: ls %t/tmp-crash/sources-* %t/tmp-crash/outputs-*
 
 
-// RUN: (cd %t && env PATH="%t/bin/:$PATH" %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -emit-library ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json 2>&1 | %FileCheck -check-prefix=CHECK-LINK %s)
-// RUN: (cd %t && env PATH="%t/bin/:$PATH" %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -emit-library ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1 2>&1 | %FileCheck -check-prefix=CHECK-LINK %s)
+// RUN: cd %t && %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -emit-library -tools-directory %t/bin ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json 2>&1 | %FileCheck -check-prefix=CHECK-LINK %s
+// RUN: cd %t && %swiftc_driver_plain -driver-use-frontend-path %S/Inputs/filelists/check-filelist-abc.py -emit-library -tools-directory %t/bin ./a.swift ./b.swift ./c.swift -module-name main -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -output-file-map=%S/Inputs/filelists/output.json -whole-module-optimization -num-threads 1 2>&1 | %FileCheck -check-prefix=CHECK-LINK %s
 
 // CHECK-LINK: Handled link
 
@@ -83,8 +83,8 @@
 // RUN: %swiftc_driver -save-temps -driver-print-jobs %S/../Inputs/empty.swift %t/a.o -lto=llvm-full -target x86_64-apple-macosx10.9 -driver-filelist-threshold=0 -o filelist 2>&1 | tee -a %t/forFilelistCapture | %FileCheck -check-prefix FILELIST %s
 // RUN: sed 's/.*-output-filelist //' %t/forFilelistCapture | sed 's/ .*//' | tail -2 | head -1 > %t/output-filelist
 // RUN: sed 's/.*-filelist //' %t/forFilelistCapture | sed 's/ .*//' | tail -1 | head -1 > %t/input-filelist
-// RUN: cat $(cat %t/output-filelist) | %FileCheck -check-prefix OUTPUT-FILELIST-CONTENTS %s
-// RUN: cat $(cat %t/input-filelist)  | %FileCheck -check-prefix INPUT-FILELIST-CONTENTS %s
+// RUN: cat %t/output-filelist | xargs cat | %FileCheck -check-prefix OUTPUT-FILELIST-CONTENTS %s
+// RUN: cat %t/input-filelist | xargs cat | %FileCheck -check-prefix INPUT-FILELIST-CONTENTS %s
 
 // FILELIST: swift
 // FILELIST-DAG: -emit-bc